Cant create bootup disk

I have true image 8 build 937
I am trying to create a bootable cd but keep getting an error message when I press the proceed button in the wizard. The message I get is "Error burning the bootable CD-R,CD-RW If I press Ok the application closes. The media is OK I've tested it in my dvd writer and also my cd writer and it will accept data from either. So why am I getting this message?